Abstract: In the cultivation of mushrooms from an underlying bed containing mushroom spores, novel compositions and processes are provided for a casing layer which is placed over the compost layer containing spawning mycelium. A hydrophilic, thermosetting prepolymer resin is mixed in with a casing substrate, preferably Canadian peat, other optional additives and sufficient amount of water to form a slurry, and the mixture is allowed to cure to a spongy block. The cured material is then pulverized and deposited as a casing layer over the compost layer. Because of the high water retention qualities of this material, watering the mushroom beds is reduced by a factor of three or more, thereby reducing operation and production costs, as also the incidence and severity of disease and displeasing blemishes.

Abstract: An apparatus for shielding the tapping cuts of rubber trees from rainwater is disclosed, which comprises an aluminum foil strip sufficiently malleable to conform to the pattern of the bark of the tree to which it is affixed. The foil strip is preferably pleated, folded or wrinkled so as to provide for sufficient elongation to accommodate both the perimeter of the bark and expansion in the girth of the tree. A method for preparing the foil strip and adhering it to the tree is also disclosed.

Abstract: An actuating mechanism for sliding doors provided on the passenger side of conventional panel-type trucks, commonly called vans, is intended to be either installed in the vehicle at the time of its original manufacture, or installed at any later time, without substantial modification of the vehicle. A winch assembly (44) including two separate winding drums (74, 86) on a common shaft (87) and driven by the shaft through springs (162, 174) and a positive driver (170), is mounted over the rear wheel well of such a vehicle. A guide assembly (50) including a pulley (54) and a pivoting guide member (62) is installed in an aperture cut in the door frame. A single pulley (56) is installed at the lower rear corner of the door opening, and a guide tube (58) is installed in the door. A flexible cable (52) is connected to an arm added to the latch operating mechanism, and extends through the guide tube (58), around the pulley (56), through the guiding assembly (50) to the winch assembly (44), for opening the door.

Abstract: Presented is a window construction of the sliding window type that includes one or more panes slidable to open or close the window opening, each of the panes being pivotal in addition to being slidable to provide access to both sides of the window pane to facilitate cleaning of both sides of the glass pane from the inside of the room.

Abstract: Automatic tracking of an endless belt, such as a coated abrasive belt, is provided by fitting the belt with at least one permanent magnet, preferably of a flexible, rubber bonded sheet-like variety such as is conveniently adhered to the backside of the belt. One or more magnetic sensors positioned transversely to a longitudinal line defined by the path of the magnets as the belt is driven between rollers detect the magnets in the event the belt exceeds an allowed extent of transverse movement, in which event a control signal is generated which activates a steering mechanism causing the belt to move in the opposite transverse direction.

Abstract: A method of grinding a shoulder portion of a workpiece by a grinding wheel whose edge surface is smaller in width than the shoulder portion of the workpiece. The workpiece is rotated about a first axis and the grinding wheel is rotated about a second axis extending at an acute angle to the first axis. The rotating grinding wheel and the rotating workpiece are first relatively moved to engage the edge surface of the grinding wheel with the radially inner portion of the shoulder portion. The rotating grinding wheel and the rotating workpiece are then relatively moved to move the edge surface of the grinding wheel in a direction substantially perpendicular to and away from the first axis to grind the shoulder portion from the radially inner portion to the radially outer portion thereof by the first grinding surface of the grinding wheel.

Abstract: The cylindrical shaped helically wound storage bin is comprised of a roof unit and a side wall structure each of which is separately formed and assembled together in the field. The wall structure and the roof unit are each formed from a continuous metal ribbon member. The ribbon member of the roof unit is helically wound and continuously interlocked in a stepped dome shape with the interlocking connection of the adjacent sides of the metal ribbon constituting riser portions of the steps and a reinforcing member for the roof unit. The metal ribbon of the bin wall structure is helically wound and continuously interlocked along the adjacent sides thereof in a cylindrical shape with the interlocking connection forming a continuous rigid reinforcing rib that projects outwardly from and extends spirally about and over the full height of the side wall structure.

Abstract: A high-strength light-weight hollow boom section for a multi-section telescopic crane boom comprises a top wall, a bottom wall, and a pair of lateral walls, each lateral wall being located between the top wall and the bottom wall. Each of the four walls comprises a pair of spaced apart longitudinally extending members, a relatively thin plate extending between, overlapping and welded to the pair of longitudinal members, and a plurality of longitudinally spaced part transversely extending stiffeners of U-shaped cross-sections, each stiffener being welded to the plate and to the pair of longitudinal members. Each longitudinal member of a lateral wall is in edge-wise abutting relationship with and welded to the surface of a longitudinal member of one of the top and bottom walls. Each stiffener of a lateral wall also has its ends in abutting relationship with and welded to the surface of a longitudinal member of the top and bottom walls. Novel slide pad arrangements are also disclosed.

Abstract: An enclosure for preventing the loss of heat and moisture through a ceiling entrance. The enclosure includes a flexible envelope with a fastening means to permit ingress and egress through the ceiling entrance while insulating the ceiling with a dead air space when the entrance is closed.

Abstract: A bushing formed of insulation that can be installed in holes drilled in wood framing components, used to construct a building, such as a dwelling, these holes are drilled so plumbing pipes & electrical wiring can be installed in said framing components.Purpose of this invention is to close off & insulate these holes before the articles are installed, or after they are installed, either method would greatly reduce infiltration & heat transfer through these necessary drilled holes, reducing the energy usage in said building, helping our Countries energy conservation program.

Abstract: A baseboard has a longitudinal recess open on its wall and floor sides. The recess continues upwardly in a groove-like depression with formation of a downward directed rib on the wall side. A holder comprises a dowel insertable below the rib into a wall borehole and the end thereof which extends into the recess has an upward bent holding part engaging behind and contacting the rib and pulling the baseboard at its upper edge against the wall. A stop part arranged on the dowel is bent downward and set back relative to the holding part by the thickness of the rib. The stop part has an extension longitudinal to the dowel which rests in the recess contacting the rear side of the baseboard.

Abstract: A generally rectangular concrete building block of partially hollow construction with at least one large rectangular vertical opening extending therethrough and provided with a generally zig-zag shaped rod embedded in the interior walls and extending transversely of and formed with a transverse loop in the center of each hollow interior. In erecting a wall, a concrete footing is first poured and a plastic sheet having a row of prepunched openings is flatly arranged thereon with the openings so spaced to indicate the positions to be assumed by a series of reinforcing bars when inserted therethrough and embedded within the footing to project vertically therethrough in a row alignable with the hollow blocks.

Abstract: Included in a panel assembly are panels each having opposite side walls terminating respectively in a standing fixed male seam and a standing deformable female seam. Similar ones of these panels are laterally joined to one another in a secure manner atop underlying support elements by mounting clips disposed intermediate juxtaposed side walls of adjacent panels. Assembly is achieved by sequentially inserting an uppermost flange on the mounting clips into a groove in the male seam of a first panel prior to rotating the clips downwardly juxtaposition the panel side wall and anchoring the clips to the support elements. Then a next panel is lowered with a downwardly facing cavity on its female seam overlying the first panel male seam, followed by roll-crimping of a portion of the uppermost female seam about the innermost male seam and mounting clip flange.

Abstract: Tongue and groove boards are provided with integral spacers that permit expansion of the assembled boards without buckling, by milling on the bottom of the groove a central longitudinally extending rib of triangular cross section. Spaced portions of the rib, of total length that is most of the length of the board, are then compressed to the level of the bottom of the groove, thereby leaving a series of relatively weak projections which serve to space the boards apart the necessary distance during assembly, but which are not strong enough to resist compression upon expansion of the boards under the influence of moisture or temperature.

Abstract: A method of cleaning bottle filling devices after bottle breakage in filling stations circulating in bottle filling machines, especially counterpressure filling machines. That filling station in which the bottle breakage has occurred is freed of glass fragments by spraying liquid thereagainst, while continuing with the machine rotation and still during the same circulation. At least during the first machine circulation subsequent to the bottle breakage and the liquid spraying, the filling device is rinsed with the liquid supplied to the bottle to be filled. After discharge from the machine circulation, the filled bottle is separated from the filled bottles of the remaining filling stations.

Abstract: In envelope stuffing apparatus which has an enclosure inserting station and includes a deck at the inserting station, structure for delivering the envelope in a path of travel to the inserting station, structure for opening the envelope and structure for inserting an enclosure into the envelope; and wherein the opening structure includes a ledge for supporting the flap of the envelope above the deck, and a first finger insertable into the envelope for stripping apart from each other the front and back panels of the envelope; there is provided an improvement in the envelope opening structure. The improvement comprises: a solenoid operable in response to delivery of the envelope to the inserting station; a second finger for depressing the envelope toward the deck against the resistance of the flap supporting ledge; and a linkage assembly.

Abstract: An animal control or training halter is of generally conventional construction with the exception that the nose piece is made of a rigid, curved metal bar covered with hard rubber. In addition to the conventional chin strap of the halter, an auxiliary control rope in the form of an endless loop is provided with a lead rope connecting ring attached to it and passes through a pair of auxiliary rings attached, respectively, to the connecting rings used on each side of the halter to interconnect the cheek straps, chin strap, and the rigid nose bar. When a lead rope is connected to the control rope, it causes, by virtue of its configuration, a clamping action to take place between the chin and nose of the animal applying pressure through the rigid nose piece to the animal's nose.

Abstract: The threshing cylinder and feeder conveyor of a combine with electrohydraulic elements are controlled by a digital computer. The computer generates a proportional voltage which is input to a linear amplifier. The amplifier provides control of the spool of an electrohydraulic servovalve. The servovalve controls the speed and direction of the threshing cylinder and feeder conveyor hydraulic motor drive. Tachometer sensors provide feedback measurement of the actual speed of the hydraulic motor output shaft. Analog-to-digital converters (A/D's) interface the computer with the sensors. Control algorithms employ velocity feedback and compensation for pressure rises due to increases in the torque on the cylinder caused by the material to be threshed entering the threshing cylinder-concave region. Easy reversal of the direction of the threshing cylinder and feeder conveyor, eliminating some of the problems associated with plugging, is available with this type of speed control equipment.

Abstract: A row crop unit (10) is provided with cooperating pairs of molded belts (40), the belts (40) being supported from overhead frame members (20, 22, 24, 26) whereby the build-up of trash within the unit is minimized. A cutoff mechanism (100) is provided, the mechanism (100) being driven by a drive mechanism (110, 112, 114, 116, 118, 120) independent of the belts (40) whereby high driving torques on the belts (40) are avoided. The forward ends of the belts (40) are carried by spaced apart sprockets (56) located forwardly of the cutoff mechanism (100) to insure that standing crop material is properly gathered and engaged prior to severing by the cutoff mechanism (100).

Abstract: A haying machine has a frame on which is fixed an upright threaded spindle defining an upright axis. A nut is threaded on this spindle so that rotation of the nut on the spindle displaces it axially along the spindle. A rigid wheel support has one end fixed to the nut and another end defining a horizontal axis about which a wheel rotates. A spring assembly normally urges the wheel with the associated support nut into a predetermined angular position corresponding to straight-ahead travel of the haying machine on the spindle. In order to adjust the height of the wheel it is merely rotated in the appropriate direction about the spindle with its associated nut and support.

Abstract: A pin locking assembly for a shackle or the like wherein a pin is non-rotatably mounted in a member and is equipped with a plate rotatably mounted on one pin end for movement between removable and non-removable positions, and removable lock means releasably fixing the plate in non-removable position relative to the pin.

Abstract: An electronic fuel control system for varying the fuel flow to a gas turbine engine during the engine's acceleration. The reference speed set point of the engine's fuel controlling governor is increased as a function of the elapsed time from engine start-up and the engine characteristics so that the engine accelerates substantially along its "required to run line.

Abstract: A fuel distribution system for regulating split of fuel flow between a pilot nozzle system and a main nozzle system for a combustor includes a flow network for directing fuel from a main fuel metering valve into an unrestricted line to a small pilot nozzle orifice producing a fine fuel spray pattern at low fuel flow rates and further including a fuel splitter valve interposed between the outlet from the fuel metering valve and a fuel conduit connected to a main fuel nozzle of increased orifice size to atomize higher rates of fuel flow thereto and wherein the fuel splitter valve includes an electrically energizable component that receives a control signal of desired pilot fuel/air ratio generated by a controller in part utilizing a signal of total actual fuel flow and total actual air flow to produce the control signal to control operation of the splitter valve so as to regulate the amount of fuel flow to the main nozzle system in accordance with the control signal thereby to produce a residual flow of fuel to

Abstract: A gas turbine engine fuel control system has a three-dimensional cam which is positioned by sensed values of engine compressor inlet and outlet pressures. The cam has two profiles which respectively indicate a desired ratio of the compressor pressures and a desired fuel flow. Interlinked cam followers engage the respective cam profiles and are also responsive to a device for setting a desired engine thrust. The cam follower linkage positions a variable metering device for the engine fuel supply.

Abstract: A gas turbine engine fuel injector which burns liquid and gaseous fuel and also has a water injection system to reduce the formation of nitrogen oxides (NO.sub.x). The water can be discharged into a combustion chamber through an annular nozzle which is located between an inner annular fuel and air discharge nozzle and an outer gas discharge nozzle which comprises a circumferential row of discrete discharge nozzles. This allows the water to be injected at the most suitable point whichever fuel is being burnt. The water can also be injected into the inner annular fuel and air discharge nozzle.

Abstract: A versatile hot water supply system incorporating a feedback control network and vapor generator of the kind in which a fuel air mixture is combusted in a chamber through which water is flowed. The vapor generator produces a low pressure steam which is permitted to mix with a low pressure water supply at a controlled rate dependent upon the desired temperature and rate of flow of the resultant mixture. The steam formed in the vapor generator is a product of fuel combustion and evaporated feed-water accompanied by the noncondensibles remaining after combustion in the vapor generator. The vapor generator may be run on transportable fuels and therefore affords portability to the system. Control systems are coupled to temperature sensors and related feedback devices and permit the efficient and advantageous use of low pressure steam and condensibles to produce high temperature water at low or high pressures. An upstream, cold water reserve provides high volume, variable temperature capacity to the system.

Abstract: A system is disclosed for controlling the flow of fluid from a pair of pumps (15,15') to a steering system (11) and a pair of auxiliary load circuits (13,13'). The steering system includes valving (43) defining a variable flow control orifice (45), and the steering system normally operates with a pressure differential X across the variable orifice, and provides load pressure signals (47,49,49',53,53') representative of demand for fluid by the steering system. Fluid flow from the pumps is controlled by a pair of priority flow control valves (21,21') including a pair of valve members (27,27') each of which is biased by a spring (29,29') toward a position permitting flow to the steering system. The spring (29) exerts a biasing force equivalent to the pressure differential X while the spring (29') exerts a biasing force equivalent to a pressure differential Y, which is less than X.

Abstract: A power element assembly is disclosed for use in a liquid environment to operate devices such as valves, switches and the like wherein such assembly is provided with an elastomeric diaphragm having an integral sealing neck with internal seal beads that are sealingly retained in engagement with a piston by prescribed compression of the sealing neck at assembly.

Abstract: Apparatus for storing solar energy, including a thermal-expansion motor operating through a ratchet mechanism to compress a coil spring located in an energy cell.

Abstract: A vehicle drive system comprises at least two prime movers communicating by way of a base block with a common output shaft. The base block has a housing enclosing two parallel, cylindrical chambers, and is provided with external mounting members for mounting in the vehicle. A strengthening wall structure separating the two chambers is defined by part-cylindrical surfaces bordering the chambers. The prime movers are mounted directly at the base block, with their shafts aligned with the axes of the chambers, and a gearing within the housing has transmission elements extending through openings in the strengthening wall.

Abstract: A cryostatic device comprising an inner wall and an outer wall connected at their upper parts by a filling orifice, a vacuum being made between the two walls, wherein the tank of cryogenic liquid, which is defined by the inner wall, is divided by a separating partition into two tanks, a primary tank and a secondary tank, the secondary tank surrounding all or part of the primary tank, the filling orifice opening into the secondary tank, and the primary tank and the secondary tank communicating via an orifice located in the separating partition at a level such that the volume of the primary tank located below said orifice is approximately equal to the volume located above this same orifice in this same tank.

Abstract: Absorption cycle refrigeration processes and systems are provided which are driven by the sensible waste heat available from industrial processes and other sources. Systems are disclosed which provide a chilled water output which can be used for comfort conditioning or the like which utilize heat from sensible waste heat sources at temperatures of less than 170.degree. F. Countercurrent flow equipment is also provided to increase the efficiency of the systems and increase the utilization of available heat.

Abstract: A well type open top refrigerated display case has a primary air conduit extending around the cabinet and main fans for circulating air through the primary conduit and across the open top of the cabinet in the form of an air curtain. A column extends upwardly from and above the well type region; defrost fans are located in a defrost conduit in the column. Defrost control means are provided for energizing the defrost fans at the start of a defrost cycle to draw ambient air from above the refrigerated display case into the upper portion of the defrost conduit at a higher pressure than the air pressure in the region of the open top; a portion of the higher pressure ambient air is directed out of the defrost conduit to collide with the air curtain flowing across the open top, the flow of the air curtain being thereby reversed and caused to flow over the top of and outside the display case.

Abstract: In a process for refrigerating protein materials, the material is prepared as a viscous paste at a relatively hot temperature and applied to a refrigerated heat transfer surface on a rotating drum, the temperatures of the protein material and the drum surface having a predetermined differential to cause congealed or frozen liquid at the interface between the protein material and drum surface to initially melt and immediately thereafter congeal or freeze in order to cause adhesion of the protein material to the surface. The protein material is compressed against the drum surface to improve heat transfer characteristics and subsequently removed in a suitably refrigerated or frozen condition. Initial heating may be extended to render excessive fat or to reduce bacterial content. Opposite surfaces of the sheet of material may also be contacted by first and second refrigerated heat transfer surfaces either simultaneously or in successive order.

Abstract: A universal joint includes a unitary face seal and retainer assembly which provides a face seal for retaining lubricant and excluding contamination. The assembly determines the limits of relative movement between the trunnion and bearing block during assembly, shipment and installation such that the seal members are not damaged during assembly and the face seal is not broken during shipment and installation.

Abstract: A resilient shaft coupling having damping by liquid displacement. Resilient elements, which extend radially of the axis of rotation, are disposed between the driving and driven members of the coupling, the resilient elements being connected to the outer driven coupling member (the outer ring), and having their free ends received in axial recesses in the generated surface of the inner driving member of the coupling. Each resilient element extends between liquid-filled chambers bounded by filling elements, the liquid responding to a relative movement between the driving and driven members of the coupling by being displaced from the chamber into the adjacent chamber bounded by the resilient elements. The spring elements on their end faces have journal pins which engage, with the interposition of bearing sleeves, in corresponding bores in the outer driven coupling member, one or both of the journal pins being directly connected to the driven coupling member to rotate positively therewith.

Abstract: This invention relates to an improvement in an externally held cylindrical expander for tubular ware having a central support for radially adjustable expansible props and segment-shaped guide elements borne by the props, in particular for treating the tubular ware with liquid treatment substances, a longitudinally tapered body mounted to each end of the central support as entry and exit parts, and the guide elements extend in the longitudinal direction of the expander between the two bodies, the improvement comprising bearing means adapted to the shape of and surrounding at least in part at least the lower tapered body and including discharge apertures distributed on its interior periphery and issuing into a gap to said body for a fluid adapted to support the expander.

Abstract: An apparatus for the treatment of materials has a series of beams connected end to end and supported concentrically within a cylindrical vessel, the materials to be treated being wound on the individual beams. The vessel has an inlet at its one end for introduction of treatment liquid, a plurality of first outlets at its bottom for discharging a portion of the treatment liquid out of the vessel, and at least one second outlet at its top for discharging the remaining treatment liquid out of the vessel. Each first outlet is located centrally of one of the beams, and the second outlet is radially aligned with a joint between an adjacent pair of the beams. A pressure-control tank is disposed above the vessel and extends substantially through the length thereof. The tank is connected to the vessel by a plurality of connection pipes for liquid communication therebetween, the connection pipes being spaced apart from one another substantially at regular distances along the vessel.

Abstract: A leaf spring stress peening apparatus is composed of a first conveyor capable of transporting a plurality of leaf springs in an unstressed position. A second endless conveyor is provided to transport a plurality of leaf spring deflecting elements. The first and second conveyors are positioned so that the leaf springs on the first conveyor are deflected by the elements on the second conveyor in a shot peening area. A blast wheel is located in the shot peening area and is positioned to concentrate shot peening material on the side of the deflected spring which is in tension. The deflecting elements disengage the spring as it leaves the shot peening area.

Abstract: A method and apparatus is disclosed for removing any out-of-round condition found in deformable metal cylinders by means of gripping the vertically aligned cylinder successively between a pair of spaced apart endless conveyor belts. The metal cylinders are fed to said pair of endless conveyor belts by moving alignment means which orients each cylinder with the cylindrical axis in a vertical direction and aligns said vertically oriented cylinders in a row while being fed to the cooperating belt members. In a preferred embodiment, the cylinder alignment is accomplished with a vertical gas column while the cylinders are proceeding in a horizontal direction.

Abstract: This invention relates to an improvement in an externally held cylindrical expander for tubular ware with a central support for radially adjustable, spreading rest means and sector-shaped longitudinal elements borne by said rest means, in particular for the treatment of the tubular ware with liquid treatment means, the longitudinal elements extending between bodies tapering in the longitudinal direction, mounted between the ends of the support, and acting as entry and exit means, the improvement comprising: (a) rollers with axes of rotation transverse to the ware transport direction T mounted on the outsides of the individual longitudinal elements in transverse planes of the expander, (b) the rollers located in a common transverse plane covering the gaps between rollers located in an adjoining transverse plane, (c) the rollers from adjoining transverse planes mounted on one longitudinal element overlap by their ends at the center of the longitudinal element, (d) the other ends of the rollers project beyond th

Abstract: A compression tool for compressing a generally tubular workpiece, comprises a tool head having an open, workpiece-receiving end. A plurality of generally parallel, spaced apart movable compressing members are carried by the tool head. A stationary compression surface also carried by the tool head opposingly faces the movable compressing members. Guides are provided in the tool head for slidably mounting the movable compressing members. A ram drives the movable compressing members towards their respective maximum compressed positions, which are defined by the ram and a ram-carrying channel. This maximum compressed position generally increases in a predetermined sequence from the workpiece-receiving end of the tool head toward an interior portion of the tool head.

Abstract: A device is provided for removably and adjustably securing a vehicle to a slotted support surface of a vehicle frame straightening apparatus. The device can comprise base plate having elongated rotatable restraining members for adjustably securing the base plate to the support surface along a first axis and frame attachment means such as a clamp that is adjustable along a second perpendicular axis. The clamp is used to grip a portion of the vehicle frame.

Abstract: A pair of arms having mounting pads affixed at one end of each arm, is mounted to a press brake bed. Gauge support members are guidingly received on the arms to support a gauge bar or other gauge mounting surface for workpiece locating stops. The gauge is to be moved and maintained with the gauging edge parallel to the press brake mounting faces of the pads, and thereby, parallel to the tooling of the press brake. One of the gauge support members is driven by a motor and drive screw, and connected through flexible non-extensible tensile members to drive the other gauge support in synchronism, and thereby position the two gauge support members simultaneously and at equal distances from the press brake tooling.

Abstract: The present invention is part of a liquid gaging system and comprises an apparatus for self testing the system. Included is an excitation signal generator apparatus for providing an excitation signal and a precision reference component for providing a precise electrical load. The invention also comprises apparatus for monitoring the precision reference component. Also included is apparatus for connecting the precision reference component to the excitation signal generator apparatus and to the apparatus for monitoring.

Abstract: Apparatus for measuring gas volume delivered at rapidly varying flow rates, over wide ranges of frequency of variation in flow rates, having a chamber with an outlet, means for varying the chamber volume to cause a volume of gas to be delivered from the outlet, and means for measuring changes in the pressure in and volume of the chamber during the varying, so that the volume of gas delivered therefrom can be derived.

Abstract: A knocking sensor having a thin vibrating plate (10) receiving sound produced from an engine. The vibrating plate is applied with a piezoelectric element (11) which delivers electric output in proportion to the vibration. The resonance frequency of the vibrating plate is made same as the knocking frequency. A resonant tube (20) for forming resonating cavity is attached in front of the vibrating plate. A sound collector (30) is provided in front of the vibrating plate. A duct (50) is arranged between the sound collector and the sensor to improve sensitivity and freedom of mounting of the sensor.

Abstract: A device for detecting engine knock is disclosed. The device comprises a bipolar vibration sensor secured to a spark ignition internal combustion engine and has first and second outputs for generating respectively signals representing individual ringing engine vibrations due to engine knock and signals representing the background engine vibrations due to engine operation, separately. A smoothing circuit is connected to the second output side of the vibration sensor for forming a means value of the background engine vibration signals. A comparator circuit has a first input terminal connected to the first output side of the vibration sensor and a second input terminal connected to the output side of the smoothing circuit for comparing the mean value of the outputs of the smoothing circuit with the peak value of the ringing engine vibration signals. A utilization circuit is connected to the output side of the comparator circuit for controlling the driving condition of the engine in an optimum manner.

Abstract: A device for judging knocking strength of an engine has a sensor (1) which detects pressure variations in a combustion chamber of the engine. A rectification circuit (3) rectifies the output of the sensor (1), the output of the rectification circuit (3) being smoothed by a smoothing circuit (4) to give the envelope waveform of the output of the sensor (1). The envelope waveform is differentiated by a differentiating circuit (5), the amplitude of the output of the differentiating circuit (5) being used to detect the knocking condition.

Abstract: A knock detecting apparatus for internal combustion engines is provided with a vibrating rod of a magnetic material having a resonance characteristic in a knock frequency hand of an engine, a free end of the vibrating rod is inserted in a round through hole of a core to form an air gap between the inner surface of the round through hole and the outer surface of the vibrating rod, and the air gas constitutes a portion of a magnetic path between the core and the free end of the vibrating rod. The vibrating rod is allowed to vibrate in more than one directions and air gaps are also formed in respective vibrating directions thereby enabling to detect vibrations due to knock in more than one directions.